162 
BRITISH ENTOMOSTRACA. 
than posterior, upper margin slightly arched, and inferior 
edge somewhat sinuated. The valves are flatter than in 
almost any other species, pellucid, and quite smooth. 
The colour is of a dull white, without any spots or marks. 
The C. detecta of Muller is quite a different species from 
the Monoc. conchaceus of Jurine, though that author 
quotes them as synonymous, in which, though with hesita- 
tion, he is followed by M. Edwards. These synonyms, 
therefore, as quoted by me in the ‘ Mag. Zool. and Bot.,’ 
must be expunged. 
Hab . — Neighbourhood of London ; Pool on Beaumont 
Water, &c. ; not common. 
5. Candona similis. Tab. XIX, figs. 2, 2 a. 
Candona similis, Baird , Trans. Berw. Nat. Club, ii, 153, 1845; Ann. 
and Mag. Nat. Hist., xvii, 415, t. 9, f. 4. 
Shell somewhat elliptical in figure, flat, slightly sinu- 
ated in the middle of the lower margin, and nearly plane 
on dorsal edge. The colour is white, with two dark- 
orange spots on the back. The valves are smooth, except 
round the edges, which are fringed with rather stiff hairs ; 
these are more numerous on anterior extremity than on 
posterior. The shell is narrower posteriorly than ante- 
riorly, and is transparent. Its motion is very deliberate, 
when it walks along the plants, first putting one foot for- 
ward, and then leisurely drawing up the other. It ap- 
proaches near to the C. detecta of Muller ; the posterior 
extremity, however, is narrower than anterior, which is 
the reverse in the detecta. 
Hab . — Pond on Clapham Common, July 1846. 
Family II — CYTHERIDiE. 
Cytherinen, Roemer , Jahrbuch, 1838. 
Character . — Two pairs of antennae ; superior not fur- 
nished with the pencil of long filaments. Feet, three pairs. 
This family contains two British genera — Cythere 
and Cythereis. 
